This is the 3770th most frequent Polish word.
morskiego
"Of the sea" or "marine".
Here, 'morskiego' is used as an adjective describing 'wybrzeża' (coast), showing it belongs to or is characteristic of the sea.
Widok z klifu na horyzont morskiego wybrzeża był zapierający dech.
The view from the cliff to the horizon of the sea coast was breathtaking.
Here, 'morskiego' describes 'wiatru' (wind), denoting that the wind originates from or is typical of the sea.
Podczas sztormu mogłem poczuć siłę morskiego wiatru.
During the storm, I could feel the power of the sea wind.
Here, 'morskiego' modifies 'dna' (floor), indicating that it pertains to the sea.